The present invention relates to all terrain vehicles (ATV) and, in particular, to an improved endless track assembly that can be substituted for the drive wheels of wheeled ATV's or any two, four or other multi-wheel drive vehicle.
A variety of all terrain vehicles have been developed for recreational, commercial, farm and military use. Such vehicles can include wheels and/or endless track assemblies to achieve traction over off-road surfaces with relatively low surface pressure at the contact surfaces of the drive train.
Snowmobiles represent an example of a track-based recreational vehicle that is used on snow and ice. The tracks, however, are not readily susceptible to operation over other types of terrain (e.g. abrasive, non-frozen) and use of the vehicle is limited to certain climates and seasons of the year.
A variety of other personal ATV's that support tracks, floatation tires and/or combinations of tires and tracks are also available for year round use over woodland, wet and swampy or desert terrain. The drive trains of the track-based ATV vehicles, like snowmobiles, are typically designed for dedicated use and cannot be readily adapted to alternative uses. Wheel-based ATV vehicles supported on floatation tires work well in woodland conditions, but have difficulty traversing snow, swamp and desert terrain.
An economical conversion assembly is therefore desired to expand the operational use of wheel-based ATV's and pickup trucks. Examples of some track assemblies that can be used to convert 4-wheel drive vehicles to track vehicles are shown at U.S. Pat. Nos. 3,689,123; 4,448,273; and 5,607,210.
The present improved track assembly was developed to accommodate the foregoing need and provides a number of improved features that accommodate a wide range of vehicles offered by a number of automotive and ATV manufacturers. Collectively, the improvements permit the conversion of the ATV's over to track operation in a matter of minutes.
The improved track assembly provides 1) a resiliently biased idler wheel suspension that conforms the shape of the track contact surface to terrain changes, 2) rubber coated, plastic idler wheels, 3) a drive wheel with a radiused peripheral edge to prevent ice and mud buildup, 4) an eccentric track tensioner housing with an off-center mounted bearing that cooperate to rotate the track drive wheel/sprocket to control track tension, 5) a multi-vehicle adapter mounting plate, 6) stop limit flanges at a torsion mounting coupler, 7) a set screw restrained coupler arm, 8) track lugs shaped to direct debris away from the track suspension and drive assembly, and 9) a spring suspension assembly, that can include an additional idler wheel, linked to the fore and aft, conformal idler wheel suspensions.